In recent years, laminates of a resin and a rubber obtained by combining a resin material such as a polyamide or the like having low gas permeability and a rubber material have been conventionally used as hoses for transporting refrigerant used in car air conditioning systems and the like.
To date, the present applicant has proposed a hose in which a resin and a rubber are bonded without using an adhesive or the like (see Japanese Patent No. 4365454).
Additionally, Japanese Unexamined Patent Application Publication No. 2000-220770A describes a hose in which an innermost layer and an intermediate rubber layer are bonded without using a conventional adhesive.
However, as a result of diligent research, the present inventors found that there is still room to enhance adhesion when directly bonding a resin layer and a rubber layer.